Flexible insert for forming recesses in walls and the like



y 6, 1952 R. M. JAMES 2,596,028

' FLEXIBLE INSERT FQR FORMING RECESSES IN WALLS AND THE LIKE Filed March 29, 1949 2 SHEETS-SHEET l 172 2:: Tar fPouwr flhrwaz z lwzs' Z! 7% 644; a/ 44/4,

M y 6, 1952 R. M. JAMES 2,596,028

FLEXIBLE INSERT FOR FORMING RECESSES IN WALLS AND THE LIKE 2 SHEETS--SHEE'I' 2 Filed March 29, 1949 -prene or the like.

Patented May 6, 1952 ,FFICE FLEXIBLE INSERT FOR FORMING RECESSES IN WALLS AND THE LlKE Robert Maxwell J amcs Bufifalo, N; Y.

I Application March 29, 1949, Serial No. 84,964

Claims.

1 This invention relates to a flexible tool device suitable for use in construction-work in connection with-the formation of undercut dovetail "slots in vertical walls or other structural forms.

More particularly, this invention relates to a flexible key form suitable for use on amold lining intended to provide undercut slots in vertical walls suitable for anchoring masonry units and the like.

The instant invention contemplates the provision of a key form defining an elongate body made of hard oil-resistant rubber such as neo- The elongate body is provided with arcuate end portions each having a plurality of radially spaced tongues and'grooves formed in the upper face thereof. The general configuration of the elongate body is such as to defineaskived edge along its complete periphery which terminates in; a lip disposed on the bottom face of the key form. The bottom face of the form is recessed and extends angularly upward .into the body of the form terminating in a sharp radius hinge area surrounding a downwardly depending integral channel-like hub portion. Ijhe channel-like hub portion normally terminates short of theplanedeveioped by the lip and is preferably oonstructed to define a slot in the upper face thereof for receiving reinforcing and fastening means therein.

The reinforcement may take the form of a small steel bar defining suitable apertures thereinvention may be arranged on. the liner surface of atypical rigid mold form in staggered array,

for example along parallel vertical axes. Thus, a plastic aggregate may be introduced into the mold form in molded proximityto the key forms to form a plurality of staggered parallel vertical undercuts or dovetail niches. in the aggregate.

Niches thus formed may be advantageously employed to receive metal anchors which may be successively locked in the undercuts between progressive layers of masonry thereby securely anchoring. the masonry to the concrete wallto ,form an integrated wall structure.

It is an object of this invention to provide a keyform, having the characteristics aforementioned which may be carried upon the liner surface of rigid mold form and simultaneously withdrawn from a hardened concreteconglomcrate upon the stripping of the rigid mold form I away. from the conglomerate.

Another object of my invention is to, provide a flexible tool device for forming. undercut slots in verticalwalls suitable for anchoring masonry units.

A further object of my invention is to provide 2 new and useful mold forms characterized by the provision of a plurality of flexible key forming tool devices arranged in staggered'array in-a predetermined pattern.

Still another object of the present invention is to provide a method of producing an integrated wall structure including a concrete backing with masonry firmly anchored thereto.

It is believed that the methods practiced in connection with the present invention will -be most clearly understood through a description of the apparatus provided for practicing same.

Many other objects and advantages of the present invention will become manifest to those versed in the art upon making reference to the following detailed description and accompanying drawings in which Figure 1 is a fragmentary isometric view showing the production of an integrated wall structure having a concrete backing and masonry work firmly anchored thereto in accordance with teachings of the present invention;

Figure 2 is a fragmentary plan view partly broken away of a flexible tool device embodying the principles of my invention;

' Figure 3 is a fragmentary side elevationalview of the device shown in Figure 2;

Figure 4 is a fragmentary bottom view ofthe device shown in Figures 2 and 3;

Figure 5 is an exploded viewillustrating the order of assembly of a complete-flexible tool device embodying the principles of my invention;

Figure 6 is a fragmentary cross-sectional view showing the structure of Figure 5 attached to the liner surface of a rigid mold form and proximately surrounded by a concrete aggregate;

Figure '7 is afr-ragrnentary cross-sectional-view demonstrating the operation of my flexible tool device during the process of withdrawing same from a hardened concrete conglomerate; and

Figure 8 is a fragmentary plan View partly in section showing a metal anchor positioned in a dovetail niche formed in a concrete wall in accordance with the present invention.

As shown on the drawings:

Referring first to Figures 2, 3 and lla flexible key form is indicated generally by the reference numeral iii. Th key form in is an integral structure andpreferably takes the form of an elongate body formed of a hard. moldedoil-ra sistant rubber such as neoprene or the like.

More specifically the key form it includes an elongated body pertion l I which is terminated on each end by an arcuate portion l2.

As may be most clearly seen on Figure'B, the upperface of the form Ii? normally defines a slightly convex surface which inclines outwardly and downwardly to the outermost periphery of the-key form I ll.

Eachkey form-Hi is'so formed as to define an essentially skived peripheral edge 43 which inclines downwardly and inwardly from the outermost peripheral portion and terminates in a lip l4 disposed on the bottom face of the form Iii.

Referring particularly to Figures 4 and 5, it will be noted that the bottom face of the key form I defines a recess l surrounded by the lip l4 and having an angularly inclined wall portion IS. The angularly inclined wall portion It terminates in a sharp radius I! (Fig. 5) which forms an effective hinge area for the walls and the lip 14.

A channel-like hub portion I 7 depends into the recess l5 and terminates short of the Plane developed by the lower edge of the lip M.

The upper face of the key form H3 is provided with a deep longitudinal recess 18 (Figs. 2 and 5) in the region of the hub [7, the purpose of which will be made evident presently.

One or more apertures l9 may be provided in the bottom of the recess is extending through the hub portion l'l.

Referring further to Figures 2, 3 and 4, it will be noted that the arcuate portions I2 are provided with a plurality of radially spaced grooves 29. The grooves 23 are substantially V-shaped and have their apices aligned substantially on a common circular axis concentric with the outer periphery of the arcuate portions l2, but lying on an inner portion of the key form iii. The formation of the grooves 29 in this manner leaves the arcuate portions i2 in the form of a plurality of tongue portions 2i which are likewise radially spaced with respect to one another.

Referring now to Figures 5 and 6, a key form it is shown in connection with its relation to the method by which it may be connected a rigid mold form. A small steel bar 22 having suitable aper= tures 22a formed therein for cooperative registry with the apertures is may be seated in the recess IB and a fastener 23, such as a screw or nail may be passed through each of the corresponding apertures 22a and I9 through the bottom of the key form.

When the key form it! is initially positioned upon the liner surfac of a rigid mold form 24, the lip 14 will effectively contact the liner surface in a tight sealing relationship.v As the hub portion I! is progressively pushed down, the lip l l will tend to spread thereby increasing the tight ness of the point of juncture with the mold form 24. The lip M will also tend to be slightly deformed as may be seen in Figure 6 in such a manner as to provide a curved lip 25 in th concrete aggregate 25 at the locale in the region of g the lip M. This is highly desirable inasmuch as crumbling and fracture of a sharp lip is thus precluded.

When the fasteners 23 are firmly seated against the steel bar 22 and securely imbedded in the liner surface of the mold form 2 the key form I!) will have its hub portion l1 lie on a co-planar level with distended lip I l along the liner surface liner surface of a mold form 24 is expelled thereby producing a suction effect upon th liner surface when the key form I0 is finally secured in firm relationship to the mold form. This not only enhances the adherence characteristics between the of so-called ferro-concret forms. After the plastic concrete aggregate 25 has hardened, the rigid mold form 24 may be stripped. therefrom. The characteristics of the key form If! are such that the key forms, too, are simultaneously withdrawn from the concrete during the stripping process.

As may be seen on Figure 7, the inclined wall.

portions it, as well as the lip i4, pivotally hinge about the sharp radius l7 forming a hinge area and the key form it will therefore be contracted inwardly. In addition, as the key forms If! are withdrawn, the V-shaped grooves 20 in the arcuate portion l2 will permit an especially effective radial contraction of the tongues 21 during the removal process.

When each key form it has been completely removed from the concrete 26, the concrete surface will be characterizedby an undercut dovetailed slot or niche 23, corresponding to the configuration defined by the key form [0. Thus, a plurality of radially spaced fins 29 corresponding to the area defined by the radially spaced grooves 28 will be located in each end of the slot or niche 28. The provision of the radially spaced fins 29 greatly enhances the strength characteristics of the dovetail niche 28 inasmuch as the fins support the lip 25 and serve as a strong reinforcing means therefor.

It will be apparent, that the key forms H3 may be selectively positioned upon the liner surface of a typical rigid mold form in any kind of spaced array in such a manner as to define a predetermined casting pattern. A particularly useful type of arrangement is shown by way of illustrative example in Figure 1 wherein is shown the production of an integrated wall structure including a concrete wall backing 3| having suitable masonry work 32 positioned adjacent thereto.

As shown on the drawings, the concrete wall 3! is assumed to have been constructed with a mold form having a plurality of key forms It arranged on the liner surface of said form in staggered array along parallel vertical axes thereby producing a corresponding plurality of dovetailed vertical slots 33.

t will be evident that a metal anchor 34 having a corrugated arm portion 35 and flanged end portion 35 may be quickly inserted into a slot formed by a key form it by placing the flanged portiontt in engaged registry within the slot as shown on Figur 8. Thus, as successive layers of masonry work 32 are laidadjacent the concrete wall 35, themetal anchors 34 may be successively locked into the vertical slots 33 and positioned between the layers of masonry. v

It will be apparent that if the masonry is. laid in brick form with the useof mortar, the metal anchors 3% Will not only be imbedded inithe mortar but may be sealed within the vertical slots 33 by the mortar. g g V Although I have chosento illustrate a method of use by specifically referring to the production of an integrated wall structure having a masonry face, it should be understood that this preferred embodiment is not to be construed as a limitation of the instant invention. It is contemplated that many other modifications and uses may be made in connection with the present invention Without departing from the essential spirit thereof.

I claim as my invention:

1. As an article of manufacture, a key form defining an elongate body terminating in arcuate end portions, said key form defining a skived edge along its complete periphery terminating in a distortable lip disposed on the bottom face thereof, a bottom face in said form recessed interiorly of said lip and having a channel-like hub depending thereinto.

2. As an article of manufacture, a key form defining an elongate body terminating in arcuate end portions, said key form defining a skived edge along its complete periphery terminating in a flexible lip disposed on the bottom face thereof, and a bottom face in said form defining a recess interiorly of said lip and having a channel-like hub depending thereinto, said hub terminating short of the plane developed by said lip.

3. In an undercut forming device, a resiliently flexible elongate body defining an upper face, a lower face and a skived edge along its complete periphery, said skived edge terminating in a lip disposed on the lower face of said body, said lower face defining a recess having a channel-like hub depending thereinto, said lower face further characterized by a sharply turned radius between said hub and said lip forming a hinge area, said lip being flexibly and pivotally displaceable at said hinge area relative to said hub.

4. A resiliently flexible insert for forming an undercut slot in plastic material as it is set therearound, said insert comprising an elongate body defining a skived edge terminating in a lower distortable peripheral lip surrounding a recess formed in the lower face thereof, said lip defining a reentrant angle into the lower face of said body terminating in a sharply defined radius hinge area surrounding a centrally disposed hub portion depending generally into said recess of said lower face, said hub normally terminating short of the plane developed by said lip.

5. As an article of manufacture, a key form defining an elongate body terminating in arcuate end portions and having a plurality of radially spaced tongues and grooves formed in the upper face of said end portions, said form defining a skived edge along its complete periphery terminating in a flexible lip disposed on the bottom face thereof, a bottom face in said form defining a recess interiorly of said lip and having a channel-like hub depending thereinto, said hub terminating short of the plane developed by said lip, said hub having a slot formed in the upper face thereof for receiving reinforcing fastening means therein.

6. In combination, a flexible tool device for forming undercut anchorage dovetails in concrete forms or the like, comprising a key form made of flexible material defining an elongate body terminating arcuate end portions, said key form defining a skived edge along its complete periphery terminating in an elastic lip disposed on the bottom face thereof, and a bottom face on said form defining a recess interiorly of said lip and having a channel-like hub depending thereinto, a metal bar in said hub, and a plurality of 6 fastening means passing through said bar and said key form.

7. In combination, a flexible tool device for forming undercut anchorage dovetails in concrete forms or the like comprising, a key form made of flexible material defining an elongate body terminating in arcuate end portions and having a plurality of radially spaced tongues and grooves formed in the upper face of said end por tions, said key form defining a skived edge along its complete periphery terminating in a resilient lip disposed on the bottom face thereof, and a bottom face in said form defining a recess interiorly of said lip having a channel-like hub depending thereinto, said hub terminating short of the plane developed by said lip, and fastening means passing through said hub.

8. In combination, a flexible tool device for forming undercut anchorage dovetails in concrete forms or the like comprising, a key form made of flexible material defining an elongate body terminating in arcuate end portions having a plurality of radially spaced tongues and grooves formed in the upper face of said end portions, said key form defining a skived edge along its complete periphery terminating in a deformable lip disposed on the bottom face thereof, a bottom face in said key form defining a recess interiorly of said lip and having a channel-like hub dependingthereinto, said hub terminating short of the plane developed by said lip, said hub having a slot formed in the upper face thereof for receiving reinforcing fastening means therein, a metal bar in said slot and a plurality of fastening means passing through said bar and said key form.

9. A key form defining a skived edge along its complete periphery terminating in an extendable lip disposed on the botom face thereof, a bottom face on said form recessed interiorly of said lip and having a hub depending thereinto, said hub terminating short of the plane developed by said lip, said hub having a slot formed in the upper face thereof for receiving reinforcing fastening means adapted to engage a rigid mold form.

10. A key form having a plurality of radially spaced tongues and grooves formed in the upper face thereof, said key form defining a skived edge along its complete periphery terminating in a distendable lip disposed on the bottom face thereof, and a bottom face on said key form defining a recess having a hub depending thereinto, said hub terminating short of the plane developed by said lip, said hub having a recess formed in the upper face thereof for receiving reinforcing fastening means therein, and a fastening means passing through said key form adapted to engage a rigid mold form.

ROBERT MAXWELL JAMES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 259,863 Jewell June 20, 1882 1,470,835 Hathaway Oct. 16, 1923 1,603,917 Johnston Oct. 19, 1926 1,641,147 Barton Sept. 6, 1927 2,319,727 Duggan May 18, 1943 2,496,616 Barton Feb. 7, 1950 2,533,131 Mathis Dec. 5, 1950 

